Quiet Professionals, Noisy Machinery

An intriguing scope mount

Seen on an original Artillerie Inrichtingen AR-10 in the Springfield Armory collection. It’s a bit of a challenge to scope these, and any retro-prototype AR-15, with the charging handle “trigger” inside the carrying handle; the thing tends to get caught up in the mount’s thumbscrew.

It looks like someone figured out how to do it before this gun wound up in Springfield’s collection.

This particular AR-10 has had the carrying handle sight guards milled down to provide a flat surface for a scope mount, with a very thin scope mount screw. With the mount, but no scope, in place, the iron sights are still usable. The Springfield Armory record for this exhibit suggests that it was made for a night scope:

Weapon donated to the Museum by International Armament Corporation on 3 January 1961.

Only about 5,500 AR-10s of all types seem to have been made. This one appears to have a replacement wooden handguard, and it has the trigger-shaped charging handle found on the early ARs and Sudanese contract guns. (The Portuguese guns had a different trigger-shaped charging handle). The cotton-reinforced resin pistol grip is deformed, possibly due to age.

The exhibit label is not entirely accurate. It says:

AR10 – Developed too late to compete with the T44 and T48, the AR10, designed by Eugene Stoner, suffered from insufficient testing before being submitted. Withdrawn from trials in 1956 after a barrel blew-up, it nevertheless, impressed Gen. William G. Wyman, commanding officer of the Continental Army Command. Wyman asked Stoner to develop a .22 caliber rifle to meet Army specifications resulting from the Salvo studies

The Army not only continued to test the AR-10 (thanks to a comment by “Yank,” one report of those tests is available here: 32603044-AR-10-MIL-TEST.pdf), but Springfield actually assisted Armalite with a design for a steel barrel that came out almost as light as the composite and stainless-liner arrangement that failed in 1956 testing, according to Roy E. Rayle in Random Shots: Episodes in the Life of a Weapons Designer.

The Springfield employee firing the AR-10 at the time was James Murphy. Murphy was not injured; the AR, Number 1002, had fired 5563 rounds successfully when #5564 blew out the left side of the barrel.

Note that this very, very early AR-10 had the gas tube running along the left side of the barrel, not over the top as in subsequent ARs. The fiberglass-reinforced resin materials of the handguard are also visible in this, ahem, exploded view.

Here’s a completely different way to scope the AR-10B, a short-lived retro-styled AR from the new Armalite. (Archived AR-15.com thread). It shows one approach to scoping a gun that has to keep the area under the carrying handle clear. We don’t know if this mount would work on the NoDak Spud (NDS) prototype-AR-15 parts, but it looks like it wouldn’t work on our original AR-10 due to the different shape of the carrying handle vis-a-vis the AR-10B’s M16A2 style.

Murphy was almost certainly using heavy gloves. It is my understanding that the burst occurred during a 6,000 round endurance test. The barrel simply got too hot. Mel Johnson was observing on behalf of ArmaLite, and according to Stoner, Johnson viciously lit into the Springfield test staff.

About WeaponsMan

WeaponsMan is a blog about weapons. Primarily ground combat weapons, primarily small arms and man-portable crew-served weapons. The site owner is a former Special Forces weapons man (MOS 18B, before the 18 series, 11B with Skill Qualification Indicator of S), and you can expect any guest columnists to be similarly qualified.

Our focus is on weapons: their history, effects and employment. This is not your go-to place for gun laws or gun politics; other people have that covered.

Why WeaponsMan?

A lot of nonsense is written about weapons, especially on the Net. Rather than rail at the nonsense, we thought we'd talk sense instead, and see how that catches on.